Many apartment complexes and layouts in Bengaluru have large gardens with flowering plants and trees. A lot of yellowing or dry leaves fall to ground everyday in such gardens, and these are swept away regularly. Hedges are also routinely pruned to maintain aesthetic appeal. This generates significant amounts of garden waste.

Many complexes dispose off garden waste to tractor operators, who pick it up, assuring it would be dumped in approved sites. Though these operators charge stiff prices, no one knows where they ultimately deposit the waste. I would like to highlight a better, responsible way of handling garden waste, based on our experience in Sobha Quartz, Bellandur.

Our apartment complex, with 146 units, has a garden spread across nearly an acre. We have a variety of trees here such as neem and jacaranda, and flowering plants like plumeria, raat ki rani and hibiscus.

Creating compost pits

In 2015, the Managing Committee of our association implemented pit composting. With this, we also stopped sending out garden waste. Until then, we used to ship out more than two tractor loads of garden waste every month, paying Rs 450 per load.

Organic matter like fallen yellow, green or dry leaves, flowers and fresh shoots from the garden, can all be turned into compost. This compost, in turn, can be valuable manure for your garden. (Kitchen waste isn’t dealt with here, though it too may be composted similarly.)

Pit composting, when done right, involves less work than building a homemade compost bin. It is also far less expensive than leaf composters that are ideal along streets, where there’s no space to dig compost pits.

How to create a compost pit?

All you need to do is grab a shovel, dig a hole, and start depositing garden waste into it – it’s that simple.

Here’s how we went about it:

• We engaged a contractor to dig pits. In just a few days, two garden waste compost pits were ready in the southwest corner of our complex – one 12 ft x 6 ft, and the other 8 ft x 6 ft, both 3 ft deep – based on available space.
• We then advised the gardener to deposit the garden waste generated everyday into one pit, and to level and water it. In any case, every part of garden gets watered once in 2-3 days, depending on the season.
• Once the deposit grew four inches, the gardener was to spread a one-inch layer of garden soil over it. For this, the soil that had been dug out to create the pits, was used. (We had kept aside some of this soil, after depositing much of it in parts of the garden with low soil levels.)
• The process was repeated until the pit was filled in about four months. Then it was covered with 3-4 inches of garden soil to as to level it with the rest of the garden. After this, the pit needs to be watered regularly once every 2-3 days.

Pit ready for closing. Pic credit: Luke Dhanaraj

• Now that the first pit was filled up and covered, the process was repeated in the second one.
• Three months after the first pit was filled up and closed, we opened it, and found the composting process complete. (Depending on the season of the year, the process may take a little longer or lesser.)
• The gardener then mined the compost from the first pit and distributed it to plants in one section of the garden, as manure. The manure was used up in just about a month. By then, the second pit was filled up, and needed to be closed. That is, the first pit was empty just in time to be filled up again. We have repeated the cycle since then.

Though we need to dig the pit and deposit waste into it, we need to remember that “nature makes the compost”!

The results – a better garden, and annual savings of Rs 25,000!

We have done several cycles of composting using the two pits so far, and this has regularly yielded fresh manure for the garden, without any additive. The manure is rich in nitrogen, potassium and phosphorous. It benefits the land by acting as a soil conditioner, fertiliser and natural pesticide. In sum, every gram of garden waste is gold!

As we have stopped using chemical fertilisers entirely, our garden is truly organic now. The natural process of composting saves mother earth from chemical pollution.

The results of this effort are truly to be seen. Our plants grow better now, with greener, healthier leaves. They flower better, and there are fewer pests around.

Our association also saves around Rs 25,000 annually. We no longer buy chemical fertilisers that would cost us around Rs 7000 a year. We save another Rs 18,000 that would have gone towards shipping out two tractor loads of waste a month, at the current rate of Rs 750 per load.

We still dispose of a small lot of garden waste, comprising twigs and sticks, once in a few months though. This is because such waste takes much longer to turn to compost.

In course of time, we also built a very ethnic, rustic and presentable fence around the pit area. This ensures that the children playing around would not inadvertently get into the space. The composting space has got christened as ‘Compost Park’!

Why is pit composting better than other methods?

• Low capex: Digging the two pits is very inexpensive, and a one-time investment of labour
• It’s easy to deposit waste and retrieve manure
• The pits have infinite life; they can last hundreds of years
• No maintenance needed
• Waste is converted to valuable manure automatically – no additives or chemicals required
• Absolutely natural, odourless process
• The compost can be used in gardens, for urban agriculture and organic farming

This model can be easily replicated in any community. Residents of several residential communities have already inspected our compost pits. And many of them, such as Sobha Lake View, have built these in their complexes.

In Part 2 of this series, we explain the step-by-step process of pit composting.